Surfers apparently care more about catching a wave than the risk of catching an infection at beaches posted with health alerts, a new Oregon State University study shows.

A Web-based survey of more than 500 Oregon and Washington surfers showed that 29 percent knowingly surfed during advisories and 40 percent didn't know if they had surfed during an advisory.

The rest said they don't surf during advisories – which warn against going in the water to swim, surf, dive or kayak because of fecal bacteria.

The study's upshot?

View full sizeOregon's beaches are dotted with unfolding signs that warn visitors of high bacteria levels. This is in Brookings.Lynn Ketchum

"Beach advisories for bacteria are not having their intended effect of dissuading surfers," co-author Anna Harding, a professor in OSU's College of Public Health and Human Sciences, told the Oregon State Extension Service. "The lack of awareness about advisories – and willingness to take risks surfing in water that may be contaminated – suggests the need to educate surfers about behaviors that make them vulnerable to illness."

Neither Harding nor study co-author Dave Stone, an OSU environmental and molecular toxicology professor, are surfers, but Harding said via email that the researchers "have heard from a number of surfers that they have had illnesses they believed were linked to surfing in potentially contaminated water."

Between 2008 and 2013, there were 357 total advisory days issued for elevated fecal bacteria detections on the Oregon coast, Harding said.

Other takeaways from the study:

Big waves: Surfers like the big waves that come with storms, but all that rain and churn can flush fecal bacteria from stormwater discharge and animal feces into the ocean – increasing the chance of getting sick.

Advisory notices: The health warnings go up online and also are posted on signs at beaches along the West Coast, but some beach entrances don't have the signs, so surfers miss them.

Sampling system: States also do sampling only intermittently – that is, not at every beach and often behind the curve of current conditions, so gaps exist.

Best advice: Surfers should "pay attention to the weather and where stormwater outfalls are located," Stone told the Extension Service. "They should also bookmark beach advisory websites with the latest information."

And don't wear earplugs: That leads to more ear infections because water still gets in and the plugs trap bacteria inside the ear canal, the researchers said.